export default {}.install = (Vue, options = {}) => {
  Vue.directive('loadmore', {
    inserted(el, binding) {
      // 获取element-ui定义好的scroll盒子
      const SELECTDOWN_DOM = el.querySelector('.el-select-dropdown .el-select-dropdown__wrap');
      SELECTDOWN_DOM.addEventListener('scroll', function() {
        const CONDITION = this.scrollHeight - this.scrollTop - 20 <= this.clientHeight;
        if (CONDITION) {
          binding.value();
        }
      }, true);
    }
  });
};
